Electronic device and lead frame

ABSTRACT

A lead frame facilitates the handling, positioning, attachment, and/or continued integrity of multiple dies, without the use of multiple separate parts, such as jumpers. The lead frame includes a number of structures, each of which is attached to at least one lead. At least one receiving surface, arranged to receive a die, is associated with each structure. When dies are disposed on the receiving surfaces, anodes are similarly-oriented. A number of fingers are attached to the lead frame, and one or more electrode contact surfaces are attached to each finger. Each electrode contact surface can be positioned (for example, bent) with respect to one receiving surface, to facilitate electrical connection between the anode of a die and a lead. The lead frame may be used in connection with surface- and through-hole-mountable electronic devices, such as bridge rectifier modules.

BACKGROUND

One type of electronic device is a module. A module includes, amongother things, one or more dies (also referred to as chips), which may besemiconductor dies or other types of dies. Modules may be analog,digital, or a combination of analog and digital. An example of an analogmodule is a bridge rectifier. Several bridge rectifier modules areavailable from Vishay Intertechnology, Inc.

FIG. 1A is a simplified diagram of a typical bridge rectifier circuit.As shown, four rectifier dies are connected to each other byelectrically conducting members. A positive DC (+) output terminal isconnected to the cathode (N-type contact of die) of two of therectifiers, while the negative DC (−) output terminal is connected tothe anode (P-type contact of die) of two of the rectifiers. The two AC(˜) input terminals are each connected to an anode of one rectifier andthe cathode of another rectifier. FIG. 1B is a cross section of arectifier die that is used in bridge rectifier modules. The rectifierdie is a single crystal semiconductor where the anode side is referredto as p-type and the cathode side is referred to as n-type. The surfacesof both sides of the die have thin metal layers that act as electricallyconducting contacts. There is also a passivation layer (such as glass orSiO₂) that protects the junction. A concern is if a large metal contactis in contact with the passivation later it may cause the passivationlayer to crack because of differences in thermal expansion when themodule heats up during normal operation.

Module packaging generally includes an exterior housing that protectsthe dies associated with the module. An example of an exterior housingis an epoxy housing. A number of leads, generally two or more leads,extend from the housing. The leads facilitate electrical interconnectionbetween the electrodes of the dies and electronic components external tothe module. The leads are configured to allow the module to be mountedto a substrate using various techniques, such as through-hole-mountingor surface-mounting techniques.

The leads extending from the housing are connected to the electrodes ofthe dies within the housing using various techniques. A lead frame is atype of packaging that can be used to provide such connection(s).Designing a lead frame that facilitates the efficient and reliablehandling, positioning, and attachment of multiple dies is desirable. Forexample, it often desirable to use automated processes to concurrentlyload and attach multiple dies onto a lead frame. It is also oftendesirable to monitor the quality of the attachment (made by soldering,for example) between the lead frame and the electrodes of the dies.

Some existing lead frame designs reduce the throughput and/or increasethe cost of producing modules, especially when automated loading andattachment processes are used. Generally, bridge rectifier modules areconstructed with either two similar lead frames or a single lead framewith separate metal jumpers between the dies and portions of the leadframe. For example, one lead frame design requires electrodes of dies tobe oriented in different directions. In general, only similarly orienteddies are concurrently loadable using automation—when the dies aredifferently oriented, automated loading efficiency is reduced. Manualloading is generally less efficient than automated loading. In addition,when dies are oriented in different directions, disparate stresses ondie passivation may occur. This is sometimes referred to as the“sandwich effect”. The sandwich effect may cause quality or reliabilityproblems.

Another type of lead frame is composed of more than one piece or morethan one lead frame. For example, die pad structures may be designedhaving two or more pieces, and/or separate jumper structures may be usedto connect the electrodes of the dies to the leads. In one example, whenfour rectifier dies are placed between two lead frames, two of the dieshave the p-type (anode) contact facing upwards and the other two dieshave the n-type (cathode) contact facing upwards. In another example,all four dies have their anodes facing upwards. The anode of each die isconnected with a small metal jumper to the appropriate portion of thelead frame. Since the metal jumpers are small, they are difficult tohandle for automated soldering equipment. Also, these jumpers may shiftduring the soldering process and contact the passivation layers of thedies, resulting in reliability problems. Also, additional solder jointsare used between each jumper and the lead frame, which may adverselyaffect the power-handling capability of the device, because solder has ahigher thermal resistance than copper. When lead frames have more thanone piece, the likelihood of part positioning errors (and subsequentreliability problems) is increased. Part positioning errors can lead toreliability and production problems, including soldering problems, whichresult in increased costs and reduced throughput. Having die surfaceshidden from view may make inspection difficult.

It will be appreciated that the claimed subject matter is not limited toimplementations that solve any or all of the disadvantages of specificlead frames or aspects thereof.

SUMMARY

Aspects of surface- and through-hole-mountable electronic devices, suchas bridge rectifier modules, are discussed herein. In particular,apparatuses for mounting a number of dies, and methods for manufacturingelectronic devices that use the apparatuses, are disclosed. In oneimplementation, an apparatus includes a lead frame. The lead framefacilitates the handling, positioning, attachment, and/or continuedintegrity of multiple dies, without the use of multiple separate parts.

The lead frame includes a number of structures, each of which isattached to at least one lead. At least one receiving surface, arrangedto receive a die, is associated with each structure. A receiving surfacemay be attached to or formed on a structure, for example. When dies aredisposed on the receiving surfaces, anodes of the dies are oriented inthe same direction.

The apparatus further includes a number of fingers (each of which may becomposed of one or more segments) and a number of electrode contactsurfaces. Each finger has two ends, which, depending on the segmentstructure of the finger, may be contiguous or non-contiguous. One end ofeach finger is attached to the lead frame. One or more electrode contactsurfaces are attached to the other end. Each electrode contact surfacecan be positioned with respect to one receiving surface, to facilitateelectrical connection between the anode of a die and a lead. A fingermay be bendable at the attached end, for example, to superpose anelectrode contact surface over a receiving surface. The electrodecontact surface may be attached to the anode via a bonding process, suchas soldering. When the surface area of an electrode contact surface isless than the surface area of a semiconductor device, solder joints areinspectable for quality assurance.

This Summary is provided to introduce a selection of concepts in asimplified form. The concepts are further described in the DetailedDescription section. Elements or steps other than those described inthis Summary are possible, and no element or step is necessarilyrequired. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended foruse as an aid in determining the scope of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a simplified diagram of a typical bridge rectifier circuit.

FIG. 1B is a cross section of a rectifier die that is used in bridgerectifier modules.

FIG. 2 is a top view of an outline of an apparatus, which includes anintegral lead frame, for mounting a plurality of dies.

FIG. 3 is a side view, in the direction of arrows 3-3, of a portion ofthe apparatus shown in FIG. 2

FIG. 4 is top view of the apparatus shown in FIG. 2, after the electrodecontact surfaces have been positioned with respect to the receivingsurfaces.

FIG. 5 is the top view shown in FIG. 4, further illustrating thedirections of arrows 6-6, 7-7, 8-8, 9-9, 10-10, and 11-11, on which thecross-sectional views depicted in FIGS. 6-11 are based.

FIG. 6 is a cross-sectional view, in the direction of arrows 6-6, of theapparatus shown in FIG. 5.

FIG. 7 is a cross-sectional view, in the direction of arrows 7-7, of theapparatus shown in FIG. 5.

FIG. 8 is a cross-sectional view, in the direction of arrows 8-8, of theapparatus shown in FIG. 5.

FIG. 9 is a cross-sectional view, in the direction of arrows 9-9, of theapparatus shown in FIG. 5.

FIG. 10 is a cross-sectional view, in the direction of arrows 10-10, ofthe apparatus shown in FIG. 5.

FIG. 11 is a cross-sectional view, in the direction of arrows 11-11, ofthe apparatus shown in FIG. 5.

FIG. 12 is a flowchart of a method for manufacturing an electronicdevice that includes the apparatus shown in FIG. 2.

DETAILED DESCRIPTION

Turning to the drawings, where like numerals represent like components,FIG. 2 is a top view of an outline of an apparatus 200 for mounting aplurality of dies (not shown). For exemplary purposes, each diediscussed herein is assumed to have the same basic configuration asillustrated in FIG. 1B. As such, each die includes a base material,which may be a semiconductor material or another type of material, andat least two electrodes, an anode and a cathode, which are used to makeelectrical contact with one or more circuits on the die.

Referring again to FIG. 2, elements of apparatus 200 are brieflyintroduced, and the elements are discussed in further detail below.Apparatus 200 includes leads 202, 204, 206, and 208. Optional housingattachment regions 217 form part of each lead.

Apparatus 200 also includes structures 212, 214, and 216, each of whichis attached to at least one lead 202, 204, 206, or 208. As shown,structure 212 is integral with leads 202 and 204; structure 214 isintegral with lead 206; and structure 216 is integral with lead 208.Together, the leads and structures form a lead frame.

The apparatus further includes a number of receiving surfaces 222, 224,226, and 228, each of which is arranged to receive a die. At least onereceiving surface is associated with each structure 212, 214, and 216.As shown, receiving surfaces 222 and 224 are associated with structure212; receiving surface 226 is associated with structure 214; andreceiving surface 228 is associated with structure 216.

Still further, apparatus 200 includes a number of fingers 230, 232, and234, which are attached to the lead frame. Each finger meets either aparticular lead or a particular structure at one end of the finger. Asshown, finger 230 meets and is integral with structure 214 at bendableregion 231; finger 232 meets and is integral with structure 216 atbendable region 233; and finger 234 meets and is integral with lead 204at bendable region 235.

A second end of each finger has at least one electrode contact surfaceattached thereto. As shown, electrode contact surface 240 is attached toand is integral with finger 230; electrode contact surface 242 isattached to and integral with finger 232; and electrode contact surfaces244 and 246 are attached to and integral with finger 234. Each electrodecontact surface is positionable with respect to one receiving surfacevia bending of a finger at a bendable region. Electrode contact surfaces240, 242, 244, and 246 have optional attachment areas or surfaces 241,243, 248, and 247, respectively, attached thereto or integral therewith.

In the discussion herein, it will be appreciated that variousconfigurations of leads, structures, receiving surfaces, fingers andelectrode contact surfaces may be used, and that the distinction betweensuch elements is generally functional and/or logical, rather than purelystructural.

Referring in more detail to leads 202, 204, 206, and 208, the leads arearranged to extend from a package (not shown) that includes a housing(not shown) within which dies are disposed. The leads facilitateelectrical interconnection between electrodes of the dies and externalelectronic components (not shown) in well-known manners. In oneimplementation, the leads are arranged to allow the device to be mountedto a substrate using through-hole-mounting or surface-mountingtechniques. As shown, the leads are arranged so the device can besurface-mounted. As shown, lead 202 is an anode lead, lead 204 is acathode lead, and leads 206 and 208 are alternating current (“AC”)leads. Any arrangement of leads now known or later developed ispossible, however. The leads are generally composed in whole or in partof a conductive material, such as copper.

Optional housing attachment regions 217 are places at which the housingmay be received by (for example, attached to) the lead frame. As shown,housing attachment regions 217 are vertical segments (with respect tothe leads) formed at places where leads 202, 204, 206, and/or 208 areintegral with structures 212, 214, and/or 216. In alternativeimplementations, housing attachment regions 217 may be located elsewhereand/or may have different configurations.

Referring to structures 212, 214, and 216 in more detail, the structuresare substantially flat surfaces arranged in a particular pattern oforganization and attached to one or more leads. As shown, structure 212is integral with leads 202 and 204; structure 214 is integral with lead206, and structure 216 is integral with lead 208. The structures aregenerally composed in whole or in part of a conductive material, such ascopper. The number, surface characteristics, pattern of organization,materials, and method(s) for attachment of the structures areimplementation-specific details that may be determined on adevice-by-device basis.

Receiving surfaces 222, 224, 226 and 228 are attached to structures 212,214, and 216. In one implementation, receiving surfaces are formed on,or integrally with, the structures, although other attachment techniquesare possible. The receiving surfaces are generally composed in whole orin part of a conductive material, such as copper.

As shown, receiving surfaces 222 and 224 are formed on structure 212;receiving surface 226 is formed on structure 214; and receiving surface228 is formed on structure 216. Each receiving surface is arranged toreceive one die in such a manner that the anode of the die does not meetthe receiving surface. In one implementation, the anode is opposed tothe receiving surface. In the context of apparatus 200, one die isdisposable on each receiving surface with the anode facing upwards andthe cathode in contact with receiving surface/die pads 221 (dies areshown on receiving surfaces in connection with FIG. 4). Die pads 221facilitate electrical interconnection between the lead frame and a diein accordance with well-known manners and techniques. Die pads 221 maybe any desired geometric shape. Die pads 221 having circular/sphericalgeometries are shown. Die pads 221 may be integral with receivingsurfaces 222, 224, 226, and 228 (and/or associated structures 212, 214,and 216), or may be attached thereto. Die pads 221 are generallycomposed in whole or in part of a conductive material, such as copper.

It will be understood that receiving surfaces 222, 224, 226 and 228represent all or part of the areas depicted (for exemplary purposes assquares) in FIG. 2. For example, a particular receiving surface may bedeemed to be the entire area on a particular structure that is occupiedby a die. Alternatively, a particular receiving surface may be deemed tobe only one or more die pads 221. In a further alternative, a particularreceiving surface may be any combination of all or part of such areas.

Referring to fingers 230, 232, and 234 in more detail, each finger maybe formed in whole or in part of any desired material, such as copper,and may include one or more straight or non-straight (for example,curved), integral or attached segments. The segments (discussed furtherbelow) may be in any desired configuration(s) or orientation(s) withrespect to the lead frame and/or each other. Each finger is bendable inat least one location. As shown, finger 230 is bendable at bendableregion 231, finger 232 is bendable at bendable regions 233, and finger234 is bendable at bendable region 235. It will be appreciated thatbendable regions may be located in different places on the fingers thanare illustrated herein.

In the context of apparatus 200, finger 230 is formed of twosubstantially straight integral segments 250 and 251. Segment 251 isonly partially visible in FIG. 2, and is shown (in a bent configuration)in more detail in FIG. 6, which is discussed further below. In an unbentconfiguration, segment 250 has an end that is co-planar and integralwith structure 214 at bendable region 231. Segment 250 extends at aright angle from, and is co-planar with, one side of structure 214.Segment 251 extends, at one end, at an (obtuse) angle from segment 250in an upward direction. Electrode contact surface 240 is attached at (asshown, formed integrally with) the other end of segment 251, and formedin a plane parallel to a plane associated with the lead frame—morespecifically, in a plane parallel to the plane of structure 212.

Finger 232 is also formed of two substantially straight integralsegments 252 and 253. Segment 253 is only partially visible, and isshown (in a bent configuration) in more detail in FIG. 8, which isdiscussed further below. In an unbent configuration, segment 252 has anend that is co-planar and integral with structure 216 at bendable region233. Segment 252 extends at a right angle from, and is co-planar with,one side of structure 216. Segment 253 extends, at one end, at an(obtuse) angle from segment 252 in an upward direction. Electrodecontact surface 242 is attached at (as shown, formed integrally with)the other end of segment 253, in a plane parallel to a plane associatedwith the lead frame—more specifically, in a plane parallel to the planeof structure 212.

Finger 234 is formed of four integral segments 254, 255, 256, and 257.Segments 255 and 257 are only partially visible in FIG. 2, and are shownin more detail in FIG. 3 (in an unbent configuration) and FIG. 7 (in abent configuration). Segment 254 is L-shaped and, in an unbentconfiguration, has an end that is co-planar and integral with lead 204at bendable region 235. Segment 254 extends at a right angle from oneside of lead 204.

Segment 255 is illustrated, in an unbent configuration, in FIG. 3, whichis a side view of finger 234 shown in FIG. 2, in the direction of arrows3-3. As shown in FIG. 3, with reference to plane 300 of lead 204 (shownin FIG. 2), segment 255 is partially curved, and extends, at one end, atan acute angle from segment 254 in a downward direction. Segment 256extends, at one end, from segment 255 in a plane parallel to plane 300.Segment 257 extends, at one end, at an (obtuse) angle from the other endof segment 256 in an upward direction. Electrode contact surfaces 244and 246 (only 246 is visible in FIG. 3) are attached at (as shown,formed integrally with) the other end of segment 257, and formed in aplane parallel to a plane 300—more specifically, in a plane parallel tothe plane of structure 214 and/or 216 (structures 214 and 216 are shownin FIG. 2).

Referring again to FIG. 2, electrode contact surfaces 240, 242, 244 and246 are discussed in further detail. Electrode contact surfaces 240,242, 244, and 246 represent all or part of elements referred to as beingattached to fingers 230, 232, and 234. For example, the electrodecontact surfaces may be considered to be those surfaces (that may beintegral with the fingers), which are formed in planes associated withthe lead frame. Alternatively, the electrode contact surfaces maythemselves be areas or surfaces integral with, or attached to, suchsurfaces. Examples of such areas or surfaces are areas/surfaces 241,243, 248, and 247, which are shown as circles/spheres, but which mayassume any desired geometrical configurations. The electrode contactsurfaces are generally composed in whole or in part of a conductivematerial, such as copper.

Each electrode contact surface is positionable, either manually or usingautomation, with respect to one receiving surface. As shown, electrodecontact surface 240 is positionable with respect to receiving surface222 via bending of finger 230 at bendable region 231. Electrode contactsurface 242 is positionable with respect to receiving surface 224 viabending of finger 232 at bendable region 233. Electrode contact surface244 is positionable with respect to receiving surface 228 via bending offinger 234 at bendable region 235. Electrode contact surface 246 ispositionable with respect to receiving surface 226 via bending of finger234 at bendable region 235.

FIG. 4 is top view of the apparatus shown in FIG. 2, after electrodecontact surfaces 240, 242, 244, and 246 have been positioned withrespect to receiving surfaces 222, 224, 226, and 228 (the receivingsurfaces are not visible in FIG. 4), respectively. As shown, dies 402,404, 406, and 408, each configured like the die shown in FIG. 1B, havinganodes (not visible) and cathodes (not visible), are disposed on thereceiving surfaces, in such a manner that the anodes of the dies do notmeet (for example, are opposed to) the receiving surfaces. Contacts 461,463, 465, and 467 are shown.

From the perspective of the top view shown in FIG. 4, FIG. 5 illustratesthe directions of arrows 6-6, 7-7, 8-8, 9-9, 10-10, and 11-11, on whichthe cross-sectional views depicted in FIGS. 6-11 are based.

FIG. 6 is a cross-sectional view, in the direction of arrows 6-6, of theapparatus shown in FIG. 5. In one aspect, FIG. 6 illustrates finger 230(composed of segments 250 and 251) in a bent position. When finger 230is bent at bendable region 231 (not visible; shown in FIG. 2), segment250 is in contact with structure 214, and electrode contact surface 240is superposed over receiving surface 222 and over die 402. In anotheraspect, FIG. 6 illustrates the superposition of electrode contactsurface 246 over receiving surface 226, when die 406 is disposed onreceiving surface 226. Electrode contact surface 246 is positionable bybending finger 234 (not visible) at bendable region 235 (not visible).FIG. 7, which is a cross-sectional view of the apparatus shown in FIG.5, illustrates finger 234 (composed of segments 254, 255, 256, and 257)in a bent position.

FIG. 8 is a cross-sectional view, in the direction of arrows 8-8, of theapparatus shown in FIG. 5. In one aspect, FIG. 8 illustrates how segment254 of finger 234 (shown in FIG. 7) meets lead 204 when finger 234 is ina bent position. In another aspect, FIG. 8 illustrates finger 232(composed of segments 252 and 253) in a bent position. When finger 232is bent at bendable region 233 (not visible; shown in FIG. 2), segment252 is in contact with structure 216, and electrode contact surface 242is superposed over receiving surface 224 and over die 404. In yetanother aspect, FIG. 8 illustrates the superposition of electrodecontact surface 244 over receiving surface 228, when die 408 is disposedon receiving surface 228.

FIG. 9 is a cross-sectional view, in the direction of arrows 9-9, of theapparatus shown in FIG. 5. FIG. 9 illustrates in another view howsegment 254 of finger 234 (shown in FIG. 7) meets lead 204 when finger234 is in a bent position.

FIG. 10 is a cross-sectional view, in the direction of arrows 10-10, ofthe apparatus shown in FIG. 5. In one aspect, FIG. 10 illustrates thesuperposition of electrode contact surface 240 over receiving surface222, when die 402 is disposed on receiving surface 222. In anotheraspect, FIG. 10 illustrates the superposition of electrode contactsurface 242 over receiving surface 224, when die 404 is disposed onreceiving surface 224. FIG. 10 further illustrates segment 256 of finger234 (shown in FIG. 7), when finger 234 is bent at bendable region 235(not visible; shown in FIG. 2).

FIG. 11 is a cross-sectional view, in the direction of arrows 11-11, ofthe apparatus shown in FIG. 5. In one aspect, FIG. 11 illustrates howsegment 250 of finger 230 (shown in FIG. 6) meets structure 214 whenfinger 230 is in a bent position. In another aspect, FIG. 11 illustrateshow segment 252 of finger 232 (shown in FIG. 8) meets structure 216 whenfinger 232 is in a bent position. FIG. 11 further illustrates segment256 of finger 243 (shown in FIG. 7), when finger 234 is bent at bendableregion 235 (shown in FIG. 2).

FIG. 12 is a flowchart of a method for manufacturing an electronicdevice that includes the apparatus, referred to as a mounting apparatus,shown in FIG. 2. The process(es) illustrated in FIG. 12 may beimplemented (in whole or in part) using one or more general,multi-purpose, or single-purpose processors. Unless specifically stated,the methods described herein are not constrained to a particular orderor sequence. In addition, some of the described method(s) or elementsthereof can occur or be performed concurrently.

The method begins at oval 1200, and continues at block 1202, where themounting apparatus is provided.

In one sample manner of constructing the apparatus shown in FIG. 2,multiple lead frames are produced as a single sub-assembly (in an array,for example). Each lead frame is connected to the sub-assembly at one ormore points via leads 202, 204, 206, and/or 208. Each of structures 212,214, and 216 is integrally formed with at least one lead. Bendableregions 231, 233, and 235 may be formed in any desired manner, such asby stamping, cutting, or another method.

At block 1204, a die is arranged on each receiving surface, with theanode of each die not meeting the receiving surface.

In one implementation, dies 402 and 404 may be placed at the same timeon structure 212, on receiving surfaces 222 and 224, respectively. Next,die 408 is placed on structure 216, on receiving surface 228, andfinally die 406 is placed on structure 214, on receiving surface 226.Anodes of each die are facing upward, the receiving surfaces. Otherpositions, orientations, and orders of assembly are possible, however.

Next, at block 1206, each finger is bent, to position one or moreelectrode contact surfaces with respect to the arranged dies. In onesample implementation, fingers 230, 232, and 234 are bent at bendableregions 231, 233, and 235, respectively. In a bent position, electrodecontact surface 240 is superposed over receiving surface 222 and theanode of die 402, electrode contact surface 242 is superposed overreceiving surface 224 and the anode of die 404, electrode contactsurface 244 is superposed over receiving surface 228 and the anode ofdie 408, and electrode contact surface 246 is superposed over receivingsurface 226 and the anode of die 406. In one exemplary implementation,the surface areas of the electrode contact surfaces are smaller than thesurface areas of the dies over which they are superposed.

The electrode contact surface(s) may optionally be attached (bysoldering, for example), to the dies, as indicated at block 1208. Whenthe surface areas of the electrode contact surfaces are smaller than thesurface areas of the dies, it is possible to inspect the attachments(for example, the solder joints) between the dies and the electrodecontact surfaces. For example, solder joints may be visually orelectronically inspected for quality assurance purposes. It will beappreciated that dies may also be attached to the receiving surfaces,either in addition to or instead of attachment to electrode contactsurfaces.

Thus, a lead frame apparatus for mounting a number of dies, and methodsfor manufacturing electronic devices that use the lead frame, have beendisclosed. The lead frame facilitates the handling, positioning,attachment, and/or continued integrity of multiple dies, without the useof multiple separate parts, such as separate jumpers. For example, thelead frame can be used with automated die positioning and solderingprocesses, because its lack of separate parts makes it accuratelypositionable. Automated equipment may be used to fold bendable regionsover to make contact to dies, which may have solder paste appliedthereto prior to the folding. Since the fingers are an integral part ofthe single lead frame, there is no shifting during the solderingprocess—the “folded frame” technique herein described facilitates nearperfect alignment. In addition, there are no additional solder jointsassociated with separate jumpers, and the piece part count is reduced.Also, when dies are disposed on the lead frame, their anode electrodesare oriented in the same direction, so two or more dies can be loadedconcurrently, increasing assembly throughput. The copper composition ofthe lead frame results in high material utilization and generally lowcost. Also, copper improves the thermal dissipation capability of leadframe. The “sandwich effect” is mitigated by the orientation of thedies, which reduces reliability problems and increases quality. Havingelectrode contact surfaces with surface areas smaller than surface areasof the dies provides the ability to inspect soldering performance, whichreduces yield loss and costs.

Although the subject matter herein has been described in languagespecific to structural features and/or methodological acts, it is alsoto be understood that the subject matter defined in the claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claims.

The word “exemplary” is used herein to mean serving as an example,instance, or illustration. Any implementation or aspect thereofdescribed herein as “exemplary” is not necessarily to be construed aspreferred or advantageous over other implementations or aspects thereof.

As it is understood that embodiments other than the specific embodimentsdescribed above may be devised without departing from the spirit andscope of the appended claims, it is intended that the scope of thesubject matter herein will be governed by the following claims.

1. An apparatus for mounting a plurality of dies, each die having ananode, the apparatus comprising: a plurality of leads; a plurality ofstructures, each structure attached to at least one lead, the pluralityof structures and the leads forming a lead frame; a plurality ofreceiving surfaces, at least one receiving surface associated with eachstructure, each receiving surface arranged to receive a die in such amanner that when the die is disposed on the receiving surface the anodedoes not meet the receiving surface; a plurality of fingers, each fingerhaving a first end and a second end, the first end of each fingerattached to the lead frame; and a plurality of electrode contactsurfaces, at least one electrode contact surface attached to the secondend of each finger, each electrode contact surface positionable, viabending of a finger, with respect to one receiving surface in such amanner that when a die is disposed on the receiving surface, theelectrode contact surface facilitates electrical connection between theanode of the die and one of the plurality of leads.
 2. The apparatusaccording to claim 1, wherein the dies comprise semiconductor dies. 3.The apparatus according to claim 2, wherein the semiconductor dies forma rectifier.
 4. The apparatus according to claim 3, wherein therectifier comprises a bridge rectifier.
 5. The apparatus according toclaim 1, wherein the apparatus is used as a surface-mountable device. 6.The apparatus according to claim 1, wherein the apparatus is used as athrough-hole mountable device.
 7. The apparatus according to claim 1,wherein the first end of each finger has a bendable area, the bendablearea bendable to superpose the at least one electrode contact surfaceattached to the second end of each finger over the receiving surface. 8.The apparatus according to claim 1, wherein when a die is disposed on areceiving surface, and when an electrode contact surface is superposedwith respect to the receiving surface, at least part of the die isvisible.
 9. The apparatus according to claim 8, wherein a surface areaof the electrode contact surface is less than a surface area of the die.10. The apparatus according to claim 1, wherein an electrode contactsurface is solderable to an anode of a die to facilitate electricalconnection between the anode and one of the plurality of leads when thedie is disposed on a receiving surface.
 11. The apparatus according toclaim 1, wherein a number of receiving surfaces comprises at leastthree.
 12. A method of manufacturing an electronic device, the methodcomprising: providing a mounting apparatus, the mounting apparatuscomprising: a plurality of leads, a plurality of structures, eachstructure attached to at least one lead, the structures and the leadsforming a lead frame, a plurality of receiving surfaces, at least onereceiving surface associated with each structure, each receiving surfacearranged to receive a die, a plurality of fingers, each finger having afirst end and a second end, the first end of each finger attached to thelead frame and having a bendable area; and a plurality of electrodecontact surfaces, at least one electrode contact surface attached to thesecond end of each finger; arranging a die on each receiving surface insuch a manner that an anode of the die does not meet the receivingsurface; and bending each finger at the bendable area to position the atleast one electrode contact surface attached to the second end of eachfinger with respect to an arranged die.
 13. The method according toclaim 12, wherein the step of bending comprises superposing the at leastone electrode contact surface over the arranged die.
 14. The methodaccording to claim 12, further comprising: attaching each electrodecontact surface to the anode of each arranged die in such a manner thateach electrode contact surface facilitates electrical connection betweenthe anode of the die and one of the plurality of leads.
 15. The methodaccording to claim 14, wherein the step of attaching comprisessoldering.
 16. The method according to claim 12, wherein the electronicdevice comprises a surface-mountable device.
 17. The method according toclaim 12, wherein the electronic device comprises a through-holemountable device.
 18. The method according to claim 12, wherein a numberof receiving surfaces comprises at least three.
 19. The method accordingto claim 12, wherein the step of arranging comprises arranging a die oneach receiving surface in such a manner that an anode of the die isopposed to the receiving surface
 20. An apparatus for mounting aplurality of dies, each die having an anode, the apparatus comprising: aplurality of leads; a plurality of structures, each structure integralwith at least one lead, the structures and the leads forming a leadframe; a plurality of receiving surfaces, at least one receiving surfaceassociated with each structure, each receiving surface arranged toreceive a die in such a manner that when the die is disposed on thereceiving surface the anode does not meet the receiving surface; aplurality of fingers, each finger having a first end and a second end,the first end of each finger integral with the lead frame; and at leastone electrode contact surface attached to the second end of each finger,each electrode contact surface bendably positionable with respect to oneassociated receiving surface, in an unbent position, each electrodecontact surface not superposed over the associated receiving surface, tofacilitate disposing the die on the associated receiving surface, and ina bent position, when the die is disposed on the associated receivingsurface, each electrode contact surface superposed over the associatedreceiving surface to facilitate electrical connection between the anodeof the die and one of the plurality of leads.